A heat storage material is used as one of means for heating or cooling in various usages. Such heat storage material is disclosed in Patent Document 1, for example. In Patent Document 1, a heat storage material that is made of strongly correlated electron material storing and dissipating heat via solid-solid phase transition. The heat storage material is capable of storing and dissipating heat by using a phase transition enthalpy generated via transformation of a crystal structure occurring during solid-solid phase transition.
When a heat storage structure is constructed from the heat storage material, it may be difficult to secure enough strength. Especially, when used for obtaining the heat storage structure that stores and dissipates heat at a desired temperature, the material may be limited to a strongly correlated electron material having a phase transition temperature corresponding to the desired temperature. Accordingly, characteristics of the strongly correlated electron material may be limited, and a desired strength may not be obtained.